CLASSIFICATION.

(Continued from page 71.)

EXOGENOUS and Endogenous, are certainly long and hard words. It is a necessary evil which afflicts Botany as well as other branches of science, that its votaries must comprehend and remember a variety of such. I have, however, found in my own case, and I have no doubt others have experienced the same in theirs, that an intimate acquaintance with scientific terms, not only reconciles us to their use and makes us regard them with favor, as correct and expressive, but also, in time, leads us to admire them as beautiful. They

are like those men with whom we often meet, who, although repulsive and disagreeable at first sight, soon win our love and respect by the many estimable qualities of mind and heart, which we discover them to possess.

But even if this were not so, if these terms were in reality and in perpetuity, as harsh and pedantic sounding as many consider them, still, as Science is no longer confined to the cell of the monk and the garret of the philosopher, but become a free denizen of the active world, and a welcome guest in the drawing room, a due regard to his own character and convenience, requires that every one should pay his respects to her. To be entirely un

acquainted with her and her language, is, at the present day, as fatal to ones' reputation, even in fashionable circles, as being a stranger to the leaders of the ton. Ignorance is, in "this nineteenth century" as much out of place in good society, as boots in a ball room, or a hunting suit at an evening party.

Beware then, dear reader, of exhibiting or of even feeling, any thing like aversion to these long words, though you may think them uncouth. Don't, I beg of you, skip what I have to say about them. It is important that you should know something about them, and you can learn them and their meanings, much more easily than you can induce people not to use them. Those reformers who would exclude from scientific no

menclature, all words but the short and easy Saxon, may labor very hard at their work of simplification, and end as they began, with making themselves ridiculous. He was probably one of them, who confounded Endogenous with Indige. nous, and taught his disciples that it meant "growing in one's own country."

Perhaps none, of all the striking differences which God has established in the outward world between nature as she exhibits herself in the torrid, and nature as she exhibits herself in the temperate regions of the earth, is more remarkable than that which appears in the structure and growth of the trees pertaining to each. It is the difference between the sturdy oak with its mighty, out-spread, far-reaching arms, and the Babel-like, heaven

aspiring palm, pushing straight upwards its branchless trunk, and bearing at its summit in one great cluster, its flowers, its foliage and its fruit. It is the difference between exogenous and endogenous plants. In figures 1 and 2 our artist has well portrayed it and I will now endeavor to explain it in words.

The names by which English botanists were for many years accustomed to distinguish the two classes of Plants which form the subject of this article, were even worse as regards length and sound than those about which we are talking, and they were much less significent and appropriate. They are fast becoming obsolete. They were invented by Linnæus, and referred to the character of the seeds. Those plants whose seeds, in germinating, split into two nearly equal parts, which in some, speedily decay beneath the ground, but in others, rise in two seminal leaves, as appears so strikingly in the common bean, just as it forces its way through the soil, were called dicoty

ledons; those which, like Indian corn, do not so split, but have the seed in one mass, and produce but one seminal leaf, were called monocotyledons; -besides these two classes was a third, of no account for our present purpose, called acotyledons, because destitute of substantial, massive seeds. It being almost always inconvenient, and sometimes extremely difficult, in classifying plants, first to ascertain the nature of the seed of each, botanists have always taken another means of determining the class. Observation taught them that they could do so without an inconvenient, microscopical examination of seeds, for the stems of all dicotyledons increase in size by successive additions to their surfaces, and all monocotyledons by additions at their centres; and that the manner of growth is, in most instances, evident from the outward appearance of the plant. Of this last fact, a single glance at figures 1 and 2 will be sufficient evidence. In order to accommodate Botanical language to the practice of botanists, M. Desfon

taines, a celebrated French naturalist, discarded the old terms, and adopted those which express the difference, not in the character of the seed, but in the manner of growth. Exogenous means growing outwardly, Endogenous growing inwardly.

Of the process of growth in these two great classes, and of their anatomical differences I will treat on another occasion.

(To be continued.)

THE AZALEA.

BOTANICAL CHARACTERISTICS;-Class, PENTANDRIA; Order, MONOGYNIA. Flowers 1-petalled, inferior; seeds in a capsule; capsule 5-celled, 5valved, opening at the top; Calyx 5-parted; Corol tubular, half 5-cleft, somewhat oblique; Stamens on the receptacle, declined; Stigma declined, obtuse, usually ending with 5 short papille.

THIS genus of plants derives its name from the

Greek azaleos, dry, but whether from the habit of some of its species, which grow and flourish on parched, arid declivities, or from the peculiar, hard, unjuicy character of its ripe wood, is matter for conjecture. It is certain however, that those who undertake to treat the genus with reference to its name, will fail. Let the earth ball in which the potted Azalea is growing, become completely dry throughout, so that the leaves begin to flag, and the plant will assuredly either die, or be so much injured that it will never thrive again.

Numerous varieties of the Azalea are indigenous to the United States, and many of them, particularly those of the A. Nudiflora, are well worthy, from their beauty, to be transplanted from our forests and woods, to our shrubberies and pleasure grounds. Many of the exotic varieties also are perfectly hardy, and even some of the greenhouse kinds will bear our winters uninjured, if planted in a sheltered position and protected with a slight covering of straw or matting. In garden cultivation the principal thing to be attended to, after planting them in a moist and rather

shady situation, is never to use the spade or hoe, but to leave the earth around them wholly undisturbed. This is necessary on account of the fine delicate fibres of the roots running along so near the surface of the ground that even a slight scraping with the hoe, will materially injure them. The weeds which appear should be pulled out by hand, and the earth allowed to become mossy.

were it not for their innocent purity in coloring and texture.

Our engraver has very successfully depicted (figure 3,) a small plant of one of the most remarkable varieties, the Azalea Indica, Variegata. The color of its flowers is, light pink with an irregularly marked white margin, and numerous dark-purple spots about the throat. It is less

No. 3.

kinds, but by the profusion its blossoms it amply pays for the trouble it occasions. A single plant two feet high, will, it is said, sometimes have from seventy to eighty of its magnificent flowers expanded at once.

The proper mode of treatment for all tender Azaleas is as follows,-1st. About one month before they are wanted for flowering, they should be transferred from the cool apartment in which they have been kept, into a warmer one, the sitting or drawing room. With the increased heat an increased supply of water becomes necessary, and still more should be given when the flowers appear, and during the whole period of flowering; care should be taken, however, that no water remains standing in the saucers.

2. As soon as they are done flowering, shift them into new pots, one size larger, using a light soil composed chiefly of sand and thoroughly decayed vegetable matter. In the process of shifting, unless great care be exercised, the delicate hair-like roots will probably be bruised or broken off, greatly to the injury of the plant. If it be necessary, as it probably will, to remove some of the old soil, it is best to wash it away, that the roots may reinain whole and sound. Ensure good drainage by a plentiful supply of potshreds in the bottom of the pot. Though fond of moisture, they are injured by stagnant water.

3. After re-potting let them continue in the warm apartment until they have secured a good growth of young wood. Frequent syringing and fresh air will materially aid them in this. When they have grown considerably they should be removed again to the cool apartment.

4. In the spring, after all danger of frosts has ceased, they should be placed in a sheltered, and somewhat shady situation, out of doors, where they should remain until Autumn, when they should be put in a light, cool apartment, to remain until wanted again to flower

PERSPIRATION OF PLANTS.

A single, large Cabbage is said to exhale by insensible perspiration seventeen times as much water as a man does. The exhalation takes place through the pores of the leaves and other green parts. Bathing then, by keeping open the pores promotes and facilitates the process of perspiring, and thus contributes to the health of the plant.